Fig. 3.

Increased DNA damage foci and cytokine expression in SMAD4 mutant fibroblasts. a DNA damage and increased expression of senescence markers in SMAD4-R496C. DNA damage in the fraction of cells with indicated numbers of nuclear 53BP1 foci are shown for three fibroblast lines by immunostaining. b Quantitative real-time PCR for PAI-1 and IL-6 in 82-6, SMAD4-WT, and SMAD4-R496C at passage 10. c Relative mRNA expression of IFNγ in 82-6, SMAD4-WT, and SMAD4-R496C at passages 19 by real-time PCR. *denotes statistical significance (*p < 0.05), n. s. denotes not significant. Error bars represent SEM